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Im finding Gold really hard i there any tips i can have im trying to figure out the atomic packing efficiency is this right and if so where do i go next?
Original post by john smilth
Im finding Gold really hard i there any tips i can have im trying to figure out the atomic packing efficiency is this right and if so where do i go next?


Yes it's about packing efficiency! There are different types of packing strictures eg. hcp- hexagonal closest-packed, ccp- cubic close packed etc. You have to find out what the two metals' structures are and then their packing efficiencies. Don't give up, you're almost there! Hope that helped
Original post by fizzers
Yes it's about packing efficiency! There are different types of packing strictures eg. hcp- hexagonal closest-packed, ccp- cubic close packed etc. You have to find out what the two metals' structures are and then their packing efficiencies. Don't give up, you're almost there! Hope that helped


What equation would you use. And thank you
Original post by john smilth
What equation would you use. And thank you

The equation is

number of atoms per cell x volume of one atom
volume of unit cell

but you really don't have to use that! I got the values by just googling and it's a lot easier haha
Original post by fizzers
The equation is

number of atoms per cell x volume of one atom
volume of unit cell

but you really don't have to use that! I got the values by just googling and it's a lot easier haha

Is there a helpful website because i'm finding it very hard to find the answers and I not smart enough to work it out. But you have been a fantastic help thank you!!!!!!!!!
Stuck on gold, someone help before i go insane :frown:
Original post by john smilth
Is there a helpful website because i'm finding it very hard to find the answers and I not smart enough to work it out. But you have been a fantastic help thank you!!!!!!!!!


Don't have a specific website but here are the percentages:
FCC (face centred cubic)- 74.05%
CCP (cubic close packed)- 74.05%
HCP (hexagonal close packed)- 74.05%
Non-close packed- 69.2%

You should be able to take it from here!
Original post by ChloeBazingaa
Stuck on gold, someone help before i go insane :frown:


Read my stuff from before!
But in case tl;dr, it's basically about packing efficiencies- how well particles are stacked in a lattice (hence the ball pit). There is a formula to figure the percentage out but from experience, it's just a lot of (unnecessary) work. Find out what structures the two metals have and then use the percentages I posted in the reply right before this to find the answer!
Ps. If you don't know what structures I'm talking about, just read the last page or so in this thread- should be very clear. Have fun!
I've got the names for the copper q molecules (with the pic of earth with '100yrs' on it) but can't find out what the numbers mean aha...
global warming potential isn't working i'm stuffed aha
Original post by Nat_LPS
global warming potential isn't working i'm stuffed aha


No! Don't give up! You're pretty much already there- it is about the global warming potential! ! Just identify the substance and you'll easily find its gwp.
Enjoy the challenges- don't get too frustrated! :cool:
Original post by fizzers
Don't have a specific website but here are the percentages:
FCC (face centred cubic)- 74.05%
CCP (cubic close packed)- 74.05%
HCP (hexagonal close packed)- 74.05%
Non-close packed- 69.2%

You should be able to take it from here!

Haha the funny thing is I got that far with my calculations but where I go from here is always wrong. Could you hint anymore or would that make it to easy. But if not that's ok because you have been a huge help.
Thank you
Original post by john smilth
Haha the funny thing is I got that far with my calculations but where I go from here is always wrong. Could you hint anymore or would that make it to easy. But if not that's ok because you have been a huge help.
Thank you


You're welcome and well I could but I want you to do the final step yourself because I mean, at the end of the day, it is supposed to challenge you.
It doesn't even require any thinking at all for goodness sake- even the wikipedia pages will have the answers! Then it's just a matter of substituting the percentages in!
Original post by fizzers
You're welcome and well I could but I want you to do the final step yourself because I mean, at the end of the day, it is supposed to challenge you.
It doesn't even require any thinking at all for goodness sake- even the wikipedia pages will have the answers! Then it's just a matter of substituting the percentages in!

Your right I have just done it. I was getting so bogged down with the complicated chemistry I just forgot how to do simple maths.


Thanks again your the best!!!!
Original post by john smilth
Your right I have just done it. I was getting so bogged down with the complicated chemistry I just forgot how to do simple maths.


Thanks again your the best!!!!


Woop woop well done! Heh thanks it's quite alright! :wink:

Ps. is your name actually john smith because pocahontas
(edited 10 years ago)
Original post by fizzers
Woop woop well done! Heh thanks it's quite alright! :wink:

Ps. is your name actually john smith because pocahontas

hahahah no i'm a doctor who fan so it's what the doctor calls him self but I wasn't meant to put in the l
Original post by john smilth
hahahah no i'm a doctor who fan so it's what the doctor calls him self but I wasn't meant to put in the l


ah! you excited for the day of the doctor then?
Original post by fizzers
ah! you excited for the day of the doctor then?

Yep going to watch in in the cinema!!!!!!
Can anyone help with silver? Ive been trying for aaggeeeeesssss.
Thanks


Posted from TSR Mobile
Original post by Swag hatter
Can anyone help with silver? Ive been trying for aaggeeeeesssss.
Thanks


Posted from TSR Mobile


Hi! How about you tell us where you're at so far? Can't really help much when it's so vague...:s-smilie:

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